This invention generally relates to a valve spacer plate for a piston-type air compressor, and more particularly to a valve spacer plate assembly which provides a gasket on each side of a plate, and a seating ledge on the plate for a reed or finger valve.
Some air compressors utilize reed or finger valves as intake and exhaust valves. These finger valves continuously flex to open and closed positions with each cycle of a compressor piston. As the piston operates through the intake stroke, air is drawn through the intake port into the compression chamber. The blades or fingers of the discharge valve block the ports to prevent any back leak of air already pumped out of the compression chamber. The incoming air impinges upon each inlet valve, permitting the inlet valve, i.e. the fingers or blades thereof, to open. In this regard, the individual fingers are lifted away from the inlet port a predetermined distance which permits the inlet air to move into the compression chamber.
When compressed air is expelled from the compression chamber, the inlet valve prevents leakage back through the inlet ports, whereby all outlet flow is only through the outlet ports. The outgoing air impinges upon the outlet valve, which would normally be blocking the outlet passage, and lifts this valve away from the outlet port thereby permitting the expelled air to leave only through the outlet port.
Typically, the fingers or blades are fixedly clamped at one end of the blade with the other blade end free to move with the lifting strokes of the compressor. The blades are of comparatively simple construction and their lift is limited, solely by a stop member.
To date many compressor designs have employed complex valve stops which are integral with a head or cylinder of a compressor. These valve stops are operable to prevent the tip of the blades from flexing past a predetermined point. However, difficult and expensive machining techniques have been required to produce these complex valve stops.
With extended compressor operating hours, the integral valve stops become worn. As a result of this wear, the valve lift is changed and the valve life is shortened. Additionally, when such wear has occurred, present compressors often require cylinder or head replacement or these compressors must be remachined.
The foregoing illustrates limitations known to exist in present compressor designs. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.